It is accepted that in today's world all atmospheric air has some degree of contaminants present in it. These contaminants may be large items, for example, blown leaves, loose papers and other debris, cottonwood tree blossoms, and insects; or the contaminants may be small enough, such as particulates, that they are suspended in the atmosphere. Examples of such particulates include dust, tree pollen, smog, and smoke particulates.
Chemical contaminants are also widely present in atmospheric air. Although many are the result of man-made pollution, other chemicals occur naturally. Typical contaminants include volatile organic compounds such as methane, butane, propane, and other hydrocarbons, also ammonia, oxides of nitrogen, oxides of sulfur, carbon monoxide, hydrogen sulfide, etc.
Most of today's machines, such as automobiles, are designed to be able to either filter out or withstand any contaminants that could cause problems to their operation. For example, large contaminants such as leaves and paper are removed from the intake air stream by the automobiles' grills and various vents. These features also remove small animals such as birds, squirrels and mice that may find their way into the engine area. Finer contaminants such as dust are removed by an air filter present in the engine compartment. For the typical automobile and internal combustion machines (such as lawn mowers, snowblowers, snowmobiles, etc.) chemical contaminants pose very little, if any, problems to the functioning of the machine, because the machine and the process by which it produces power, are capable of withstanding the presence of contaminants in the intake air.
There are some machines and systems that have not yet been optimized for operating in today's contaminated atmosphere. This may be because the importance of clean intake air has not been recognized as a requirement for efficient and/or optimal operation, or because those contaminants in the air that may degrade the performance of the machine have not yet been adequately recognized or defined.
The fuel cell, a rapidly emerging source of power for both residential and commercial purposes, is one type of system that is not yet fully understood. A fuel cell is a device consisting of two electrodes (an anode and a cathode), between which is sandwiched an electrolyte. Depending on the size, shape and design of the cell, the fuel cell is capable of providing enough energy to run a cell phone, a computer, an automobile, a residential house, or even a power plant. Fuel cells typically operate with a fuel source being supplied to the anodic side of the cell and an oxidant being supplied to the cathodic side. An example of a commonly used fuel is hydrogen.
Many fuel cells are not designed to operate efficiently in the presence of large amounts of contaminants which may be present in the intake air that is necessary for the functioning of the fuel cell. They also have not generally been designed to handle or filter such contaminants from the intake air. This is because fuel cells, and their operation, are typically new, and their operation parameters are typically not well defined. The overall capabilities and limits of fuel cells generally are not completely understood.
What is desired, therefore, is a fuel cell that functions within environments having a wide range of contaminants.